Fluid heater



' April 7, 1959 Filed Nov. 7, 1957 H. D. BOWMAN FLUID HEATER 2 Sheets-Sheet 1 /N VENT'OR HYMAN D BOWM AN ATTORNEY FLUID HEATER Filed Nov. 7, 1957 2 Sheets-Sheet 2 INVENTOR.

HYMAN D. BOWM N BMW ATTORNEY United States Patent FLUID HEATER Hyman D. Bowman, Raleigh, NC. Application November 7, 1957, Serial No. 695,159 13 Claims. (Cl. 219-33) My invention relates to heating apparatus and more particularly to a fluid heater.

In accordance with the prior art of which I am aware oil wells containing a high viscosity fluid have been heated by means of placing therein a heater which heats the fluid. A separate apparatus has been provided for extracting the heated fluid from the oil well. This system has produced an impractical solution to the problem of heating the oil as it passes up through the well because of variations in the currents thereby producing variations in the viscosity of the fluid and other reasons.

It has been usually assumed that to build a practical device for reducing the viscosity of oil in an oil well it was necessary to have a circulation of warm oil back into the well so as to warm the reservoir of oil. I have realized, however, that while the oil may be too viscous to pump through a long pipe to the surface nevertheless it is not usually too viscous to be pumped the short distance from the reservoir through a wall into a heating device.

It is accordingly an object of my invention to provide an improved oil well heating apparatus.

It is another object of my invention to provide an improved continuous fluid heating apparatus.

It is still aother object of my invention to provide an improved heating apparatus.

It is an ancillary object of my invention to provide a new and useful article of manufacture.

In accordance with the preferred embodiment of my invention I provide a device comprising a hollow substantially cylindrical container with metallic walls which is substantially elongated. Near the bottom end of said container I provide an opening for allowing fluid to enter said container. Substantially opposite said opening I provide a propelling apparatus such as a motor 3 with a pump blade 5 for moving fluid upward through the interior of said container. Above said pump blade I provide a plurality of heating coils for heating fluid as it flows upward through said container. Surrounding the upper end of said heating coils I provide an enclosed chamber which serves as a connection box and which serves to insulate the upper ends of the heating coils from the fluid in the remainder of the said chamber.

A passageway is provided for the fluid to flow around the said connection box toward the upper end of said chamber. Atthe upper end of said chamber I provide a pipe connected into said chamber for carrying fluid from inside said chamber upward through the well to the surface. In accordance with the preferred embodiment of my invention I provide a plurality of fluid transmission holes inside said chamber in said pipe.

The novel features that I consider characteristic of my invention are set forth with particularity in the appended claims. The invention itself, however, both as to'its organization and itsmethod of operation; together with additional objects and advantages thereof, will best be understood from the following description when read inconnection with the accompanying drawing in which:

Figure l is a showing partially in section of a continuous flow fluid heater in accordance with the preferred embodiment of my invention.

Figure 2 is a showing partially in section of a continuous flow fluid heater in accordance with another embodiment of my invention.

In accordance with the preferred embodiment of my invention I provide an outer shell of circular cross sec tion.

The shell comprises a first hollow cylindrical piece 2 preferably constructed of steel. A second hollow cylindrical piece 4 extends co-axially with said first cylindrical piece from a point beyond the upper end of said first hollow cylindrical piece 2 downward around said first cylindrical piece 2 so as to cover part of said first hollow cylindrical piece 2. Said first 2 and said second 4 hollow cylindrical pieces are fastened together preferably by screwing at the lower end of said second piece 4. Said first hollow cylindrical piece 2 is sufliciently smaller than said second hollow cylindrical piece 4 to allow room for fluid movement between the walls of the first and second hollow cylindrical pieces in the region where they are co-extensive. A hole 6 is provided in the wall of said first hollow cylindrical piece 2 at a point a short distance above the point where said first 2 and second 4 cylindrical pieces are joined for allowing fluid to travel from the interior of said first hollow cylindrical piece 2 into the region between said hollow cylindrical pieces.

I provide a second opening through the shell at the top of the second cylindrical piece 4 through which a pipe 8 extends for pumping fluid. The pipe extends a short distance inside the shell and then is fastened by a pair of brackets 10, 12 to a plate 14 at the end of the first hollow cylindrical piece. The fluid pipe 8 is also fastened by a collar 16 to pipe held by the bracket 10. In a preferred embodiment of my invention the fluid pipe is divided into two pieces and the said fastening comprises a collar encircling the two sections of said fluid pipe and into which the two sections of said fluid pipe 8 are screwed said bracket being welded to the top plate of the shell. In this embodiment of my invention the fluid pipe comprises two pieces, a first portion extending from the center of the last mentioned collar down into the interior of the shell and a second piece extending from the end of the first piece inside the collar upward to the surface. The collar is provided with threads for engagement with threads on said pieces of pipe so as to hold the pieces firmly in position.

In the preferred embodiment of my invention I provide at least one hole 18 in a wall of said pipe inside said shell for allowing fluid inside said shell to enter said pipe 8 after it has been heated by the electrodes.

Inside said shell near an end thereof which I shall refer to hereinafter as the bottom end and which end is opposite to the end to which said fluid pipe 8 is connected I provide a motor having connected thereto a propeller. Holes 20 are provided in the wall of said shell opposite said motor to allow circulation of fluid through said shell in around said motor for cooling of said motor. Opposite said propeller I provide a hole through said shell for allowing fluid outside of said shell to pass in to the region of said propeller. Said motor 3 and said pump blade 5 are constructed so as to cause fluid in the region of said pump blade to move upward through the interior of said shell. Above said pump blade I provide a plurality of heating elements 22. These heating elements comprise resistance type conductors coated with an insulating material preferably of a hard type and capable of standing high temperatures. Said heating elements 22 extend upward through a plate 24 into a connection box. Inside of said connection box electric wires 26 are connected to the ends of said heating elements 22 so as to apply current to said heating elements. At the upper end of said connection box there is a hole in a wall of said connection box through which passes a conduit 28 containing the electrical wires supplying the heat for said electrodes. The said conduit extends upward and passes out through an opening in the top of said shell.

In accordance with one embodiment of my invention I provide in said connection box a thermostatic control element with connections extending through the lower wall of said box to a thermostat element 30 which is responsive to temperature so as to control the current through said box in response to the temperature of said thermostat element. This thermostat element 30 is located in the fluid region so as to be responsive to the temperature of the fluid inside the shell. The temperature control device is connected to the current supply, for the electrodes 22 so as to be capable of shutting off the current to the said electrodes when the temperature exceeds a predetermined level in a manner well knownv in the art.

Also in accordance with another embodiment of my of said connection box I also provide a well 54 which comprises an elongated cylindrical hollow pipe which is closed at its lower end. This well is a thermostat well for enclosing a thermostat element which is responsive to temperature. The well is spaced away from said heating elements 52 so as to be responsive to the tempera ture of the fluid inside of the cylinder rather than to invention I provide a control element in said connection box having connections leading to a conduit which extends through the lower wall of said connection box. The said conduit carries wires leading to the motor which drives the propellers causing circulation of fluid in said box.

In the operation of my device fluid is brought into the lower portion of the shell, flows up around the heating coils up to the top of the shell and into the fluid pipe 8 through which it is pumped up to the surface. I have thus provided an apparatus for reducing the viscosity of fluids in oil wells so that they may be continuously pumped more easily. I have found that the viscosity in most circumstances is not high enough to prevent it being drawn into the chamber and it is not necessary to heat the fluid in the well before being able to pump it into the chamber. Thus while it might be assumed that such a continuous flow apparatus as I teach would be impractical, nevertheless I have found that it is an excellent solution to the problem in almost all circumstances.

In accordance with another embodiment of my invention, I provide an elongated hollow cylinder 32 having walls of a rigid material preferably steel. At each end of said hollow cylinder I provide end pieces 34, 36 which are attached to said hollow cylinder by means of bolts extending through the cylinder walls into the end pieces. Near one end of said hollow cylinder 32 which I shall call the bottom end hereinafter, is a pump 38 with a motor 40 for driving said pump. Spaced a substantial distance from said pump I provide a cylindrical box the temperature of the heating elements. The thermostat element is connected to a control box 56 wherein a control device is located for controlling the current through said heating elements in response to the current through said thermostat element. I also provide electric wires from said conduit which extend inside of one or more conduits 58 through the bottom of said connection box 42 and extending to said motor where they are connected so as to supply current to said motor. The conduits 58 enclosing the latter wires are preferably of metal so as to protect the said wires from the heat inside said cylinder. The said wires furnishing current to said motor may be connected to controls inside of said control box 56 which are responsive to said thermostat but 42 which I shall refer to hereinafter as a connection 1 box. Between the pump 38 and the connection box 42 I provide a plurality of rods 44 for maintaining a predetermined spacing between said pump and said connection box. Around said connection box 42 I provide a plurality of rings 46 having projections thereon extending radially preferably in an outward direction so as to act as spaces between the walls of said connection box 42 and the interior wall of said cylinder 32. The projections are sufliciently long to maintain sufficient distance between the main body of said rings and the wall of said cylinder to allow fluid to pass therebetween.

At the upper end of the cylinder 32 which is the end opposite that at which said pump 40 is located I provide a first hole through said end piece having a pipe 48 therethrough extending through said end piece into the interior of said cylinder. The said pipe is preferably open entirely at its end inside said cylinder. The pipe is welded on the outside of the end piece to the end piece. The said pipe extends a short distance above the upper end piece. A collar 50 is provided which engages screws on the upper end of the said pipe into which anin the preferred embodiment of my invention the current to said motor is responsive to controls outside of said hollow cylinder preferably at the surface of the well in which the said cylinder is operated.

I thus have a simple device for drawing a thick, or high viscosity, oil into said chamber, heating said fluid so as to decrease its viscosity and causing it to pass out the upper end of the cylinder through the pipe in the end thereof.

Although I have shown and described specific embodiments of my invention, I am aware that other modifications thereof are possible; my invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and the spirit of the invention.

I claim as my invention:

1. In combination, an elongated cylindrical shell including a removable top, a plurality of electric heating elements mounted in said shell, electric conductors having connections with said elements extending through a wall of said shell into the interior of said shell, said shell having therein a plurality of openings positioned below said heating elements, a fluid pump mounted in said shell below said heating elements, driving means for operating said fluid pump connected to said fluid pump, a pipe extending through the upper end of said shell into the interior of said shell, said pipe having a fluid opening therein, thermostatically operated means for controlling and regulating the temperature of said elements, said thermostatically operated means comprising a temperature responsive element inside said shell and a control device connected electrically to said temperature respon-- sive element so as to control the current through said element.

2. In combination, an elongated cylindrical shell ineluding a removable top, a plurality of electric heating elements mounted in said shell, electric conductors having connections with said elements extending through a. wall of said shell into the interior of said shell, said shell having therein a plurality of openings positioned below said heating elements, a fluid pump mounted in said shell below said heating elements, driving means for operating said fluid pump connected to said fluid pump, a pipe exgssn'sor tending through the upper end of said shell into the interior of said shell, thermostatically operated means for controlling and regulating the temperature of said elements, said thermostatically operated means comprising a temperature responsive element inside said shell and a control device connected electrically to said temperature responsive element.

3. In combination, an elongated cylindrical shell including a removable top, a plurality of electric heating elements mounted in said shell, electric conductors having connections with said elements extending through a wall of said shell into the interior of said shell, said shell having therein an opening positioned below said heating elements, a fluid pump mounted in said shell below said heating elements, driving means for operating said fluid pump connected to said fluid pump, a pipe extending through the upper end of said shell into the interior of said shell, said pipe having a fluid opening therein thermostatically operated means for controlling and regulating the current through said elements connected to said conductors.

4. In combination, an elongated cylindrical shell including a removable top, a plurality of electric heating elements mounted in said shell, electric conductors having connections with said elements extending through a wall of said shell into the interior of said shell, said shell having therein a plurality of openings positioned below said heating elements, a fluid pump mounted in said shell below said heating elements, driving means for operating said fluid pump connected to said fluid pump, a pipe extending through the upper end of said shell into the interior of said shell, said pipe having a fluid opening therein inside said shell, and thermostatically operated means for controlling and regulating the current through said elements connected to said conductors.

5. In combination, an elongated cylindrical shell com prising removable end closures, electric heating elements mounted in said shell, electric conductors connected with said elements and extending through the wall of said shell, said shell being provided with fluid passage openings to permit fluids to enter and leave said shell, a fluid pumping apparatus located in said shell, thermostatically operated means connected to said electric conductors for controlling the current through said heating elements, said thermostatically operated means being responsive to the temperature of the fluid inside said shell, a leak proof enclosure mounted in said shell enclosing said connections and controls, a pipe connected to one end of said shell, a fluid inlet opening in said pipe near an end thereof.

6. In combination, an elongated chamber having rigid walls, said container having a plurality of holes through one of said walls near an end of said chamber, an electric heating element inside said shell, a fluid pump located below said heating element capable of moving fluid toward said heating element, a pipe for transmission of fluid located inside of said chamber extending through the wall of said chamber at the opposite end of said chamber from said fluid propelling device and being anchored to said chamber, a fluid opening in a wall of said pipe inside said chamber, a conduit extending through a wall of said chamber, electric conductors extending through said conduit and being connected to said heating element, a temperature responsive control device inside said shell responsive to the temperature of the fluid in said chamber and connected to the said conductors, said temperature responsive device being capable of changing the flow of current therethrough in response to a change in temperature of the fluid in said chamber.

7. In combination, an elongated chamber having rigid Walls, said container having a hole through one of said walls near an end of said chamber, an electric heating element located inside said chamber, a fluid propelling device located between said hole and said heating element capable of moving fluid toward said heating element, a

d pipe for transmission of fluid located inside of said chamber and extending through the wall of said chamber at the opposite end of said chamber from said fluid propelling device and being anchored to said chamber, a fluid opening in a wall of said pipe near a wall of said chamber, a conduit extending through a wall of said chamber, electric conductors extending through said conduit and being connected to said heating element, a temperature responsive control device inside said shell responsive to the temperature of the fluid in said chamber and connected to the said conductors, said temperature responsive device being capable of changing the flow of current therethrough in response to a change in temperature of the fluid in said chamber.

8. In combination, an elongated chamber having walls of rigid material, said container having holes through one of said walls near an end of said chamber, electric heating elements located inside said chamber, a fluid propelling device located between said hole and said heating element capable of moving fluid toward said heating element, a pipe for transmission of fluid located inside of said chamber and extending through the wall of said chamber at the opposite end of said chamber from said fluid propelling device and being anchored to said chamher, a fluid opening in a wall of said pipe near a Wall of said chamber, .a conduit extending through a wall of said chamber, electric conductors extending through said conduit and being connected to said heating element.

9. In combination, an elongated cylindrical shell comprising removable end closures, electric heating elements mounted in said shell, electric conductors connected with said elements and extending through the wall of said shell, said shell being provided with fluid passage openings to permit fluids to enter said shell, a fluid pumping apparatus located in said shell, a leak proof enclosure mounted in said shell enclosing said connections and controls, a fluid transmission pipe connected to and extending through one end of said shell, a fluid inlet opening in said pipe near an end thereof inside said shell.

10. In combination, an elongated cylindrical shell comprising removable end closures, electric heating elements mounted in said shell, electric conductors connected with said elements and extending through the wall of said shell, said shell being provided with fluid passage openings to permit fluids to enter said shell, a fluid pumping apparatus located in said shell, a leak proof enclosure mounted in said shell enclosing said connections and controls, a pipe connected to one end of said shell, a fluid inlet opening in said pipe near an end thereof.

11. In combination, an elongated hollow cylinder comprising walls of a rigid material, end pieces at each end of said cylinder attached to and closing the ends of said cylinder, a fluid pipe fastened to a first end of said cylinder, and extending into and having an opening therein in the space enclosed by said cylinder and said end pieces, opening in a wall of said cylinder near the end opposite said first end, a heating element inside said cylinder, a fluid pump inside said cylinder positioned so as to cause fluid entering thru said opening to flow past said heating element.

12. In combination, an elongated hollow cylinder comprising walls of a rigid material, end pieces at each end of said cylinder attached to and closing the ends of said cylinder, a fluid pipe fastened to a first end of said cylinder, and extending into and having an opening therein in the space enclosed by said cylinder and said end pieces, opening in a wall of said cylinder near the end opposite said first end, a heating element inside said cylinder, a fluid pump inside said cylinder positioned so as to cause fluid entering thru said opening to flow past said heating element, electric conductors for supplying current to said elements, and control means connected to said conductors for controlling the current through said heating element.

13. In combination, an elongated shell comprising removable end closures, a one way valve extending through one of said end closures allowing fluid to leave but not enter said shell, electric heating elements mounted in said shell, electric conductors connected with said elements and extending through the wall of said shell, said shell being provided with fluid passage openings to permit fluids to enter said shell, a fluid pumping apparatus located in said shell, a leak proof enclosure mounted in said shell enclosing said connections and controls, a pipe con- References Cited in the file of this patent UNITED STATES PATENTS Germain Apr. 10, 1951 Bowman Mar. 13, 1956 

